KUNOL. SV. VET. AKADBMLENS HANDLINGAR. BAND 47. NIO 4. 



21 



drawn, in all the diagrams, somewhat higher up than is indicated. Since, however, ;< 

 variation of the relative depths will influence chiefly upon the wave-length and not very 

 much upon the qualitative appearance of the curves, we might accept the figures as a 

 pretty true representation of the motion for the case 



h = 4, ä' = 2, 

 and answering to a value a, giving the correct wave-length. 



Fig. 2. 



These curves are drawn at intervals for a t of 60° or 30°, i. e. at intervals of time of 

 half a second or a quarter of a second respectively. The current, for a/ = 0, is running 

 with its maximum intensity c leftivards, then decreases to nil for at = 90°, and finally with 

 a gradually increasing velocity is running to the right. Thus, in an obvious manner is 

 illustrated how, under those circumstances, a new wave is formed and made to travel right- 

 wards. Of course, in a similar manner, during the next half of a period, there will be 

 generated a new wave, which subsequently will advance to the left, and so on. 



The dates used correspond to 



/. = 0,r> i e, 



